1. Field of the Invention
The invention concerns a process and an instrument for stretching tissue of skin.
2. Description of the Related Art
For closing large wounds and skin defects it is known from, for example, U.S. Pat. No. 5,486,196 and U.S. Pat. No. 5,618,310 to mechanically stretch the skin surrounding the wound or the skin defect, thereby inducing accelerated tissue regeneration. Distractors are employed for this skin stretching, which are anchored in the skin and include pulling means. These pulling means transmit a pulling force to the skin tissue for stretching the skin. A higher pull force brings about a stronger tissue proliferation. A high pull force however also has as a consequence that on the pressure side, ahead of the pull means, the skin tissue is compressed. In the instrument known from U.S. Pat. No. 5,486,196 the pull force is transmitted to the skin tissue via a long inter-dermal needle, which is anchored in the skin parallel to the edge of the wound. Thereby higher pull forces can be transmitted to skin tissue, without the pressure on the pressure side of the long needle rising above a critical closure pressure of the tissue system, which could lead to ischemia of the tissue. In the case of the instrument disclosed in U.S. Pat. No. 5,618,310 the pull force is introduced via a needle stuck into the skin at one point. Accordingly, the pull force is limited such that the critical closure pressure which could lead to ischemia on the pressure side of the needle is not exceeded. This limitation on the pull force also means a limitation on the stretching of the skin, so that an optimal tissue new formation is not achieved.